import supa from '@/components/supadb/aksupainstance.uts'

/**
 * 优惠券模板模型
 */
export type CouponTemplate = {
  id?: string
  cid?: number
  merchant_id?: string
  name: string
  description: string | null
  coupon_type: number // 1:满减, 2:折扣, 3:免运费
  discount_type: number // 1:固定金额, 2:百分比
  discount_value: number
  min_order_amount: number
  max_discount_amount: number | null
  total_quantity: number | null
  per_user_limit: number
  usage_limit: number
  applicable_products: any[]
  applicable_categories: any[]
  start_time: string
  end_time: string
  status: number // 1:正常, 2:暂停, 3:已结束
  created_at?: string
  updated_at?: string
}

export type CouponQuery = {
  name?: string | null
  type?: number | null
  status?: number | null
  page?: number
  pageSize?: number
}

function getCurrentUid(): string | null {
  try {
    const session = supa.getSession()
    return session?.user?.getString('id') ?? null
  } catch (e) {
    return null
  }
}

/**
 * 分页获取优惠券模板列表
 */
export async function fetchAdminCoupons(query?: CouponQuery): Promise<{ total: number; items: CouponTemplate[] }> {
  let q = supa.from('ml_coupon_templates').select('*', { count: 'exact' })
  
  if (query?.name != null && query.name !== '') {
    q = q.ilike('name', `%${query.name}%`)
  }
  if (query?.type != null) {
    q = q.eq('coupon_type', query.type)
  }
  if (query?.status != null) {
    q = q.eq('status', query.status)
  }

  const p = query?.page ?? 1
  const ps = query?.pageSize ?? 20
  const from = (p - 1) * ps
  const to = from + ps - 1

  const { data, error, count } = await q
    .order('created_at', { ascending: false })
    .range(from, to)
    .execute()

  if (error != null) {
    console.error('获取优惠券列表失败:', error)
    return { total: 0, items: [] as CouponTemplate[] }
  }

  return {
    total: count ?? 0,
    items: (data ?? []) as CouponTemplate[]
  }
}

/**
 * 保存优惠券模板（新增/更新）
 */
export async function saveCouponTemplate(tpl: CouponTemplate): Promise<boolean> {
  const uid = getCurrentUid()
  if (uid == null) return false

  const { error } = await supa
    .from('ml_coupon_templates')
    .upsert({
      ...tpl,
      merchant_id: uid,
      updated_at: new Date().toISOString()
    })
    .execute()

  if (error != null) {
    console.error('保存优惠券模板失败:', error)
    return false
  }
  return true
}

/**
 * 切换优惠券状态
 */
export async function toggleCouponStatus(id: string, isOpen: boolean): Promise<boolean> {
  const nextStatus = isOpen ? 1 : 2 // 1:正常, 2:暂停
  const { error } = await supa
    .from('ml_coupon_templates')
    .update({ status: nextStatus, updated_at: new Date().toISOString() })
    .eq('id', id)
    .execute()

  if (error != null) {
    console.error('更新优惠券状态失败:', error)
    return false
  }
  return true
}

/**
 * 删除优惠券模板
 */
export async function deleteCouponTemplate(id: string): Promise<boolean> {
  const { error } = await supa
    .from('ml_coupon_templates')
    .delete()
    .eq('id', id)
    .execute()

  if (error != null) {
    console.error('删除优惠券失败:', error)
    return false
  }
  return true
}